"We are overwhelmed with complete happiness and love having made our eternal commitment," the couple said in a statement to People magazine. "To say 'I do' in front of family, friends and, most importantly, our children has been the happiest moment of our lives."

Simpson 33, and Johnson, 34, had postponed their wedding from last year after the singer became pregnant with the couple's second child

The bride wore a custom Carolina Herrera gown, and both of her children were involved in the ceremony -- daughter Maxwell, 2, served as flower girl, while son Ace, 1, was ring bearer.

Jessica and Eric had booked the venue three months ago, and on Friday they held a huge Fourth of July barbecue for their wedding guests.

The couple began dating in May, 2010, and were engaged just six months later.

It's the second marriage for both, Johnson married first wife Keri in 2005, while Simpson was previously married to 98 Degrees singee Nick Lachey from 2002-06.